SOLUTION: Copier A can make 300 photocopies of a page in 15 minutes.COpier B can do the same job in 12 minutes.If both copiers work together,how long will it take them to do the job?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Copier A can make 300 photocopies of a page in 15 minutes.COpier B can do the same job in 12 minutes.If both copiers work together,how long will it take them to do the job?      Log On


   

Question 389207: Copier A can make 300 photocopies of a page in 15 minutes.COpier B can do the same job in 12 minutes.If both copiers work together,how long will it take them to do the job?
Found 2 solutions by mananth, Jk22:
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
Copier A can make 300 photocopies of a page in 15 minutes.COpier B can do the same job in 12 minutes.If both copiers work together,how long will it take them to do the job?
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copier A 300 in 15 minutes
Copier A 20 copies in 1 minute
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copier B 300 in 12 minutes
Copier B 25 copies in 1 minute.
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Together they can do 20 +25 = 45 copies in 1 minute.
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300 photocopies
300/45= 6.6 minutes
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m.ananth@hotmail.ca

Answer by Jk22(389) About Me  (Show Source):
You can put this solution on YOUR website!
It will take : 1/(1/12 + 1/15) = 3*4*5/(5+4) = 20/3 = 6 + 2/3 minutes or 6 minutes 40 seconds.

The reasoning can be done like this : the copy-speed of A is 300/15 pages/minutes

B is 300/12 pages/minute, if they work together, the total speed is 300/15+300/12=20+25=45 page minutes, so for the 300 pages, it will take : 300/45 = 6,666 minutes, or 6 2/3 minutes.